Mixed

Incretin-based therapies (GLP-1RA and dual agonists) cause a mild absolute decrease in skeletal muscle mass and strength, but this is offset by a disproportionately larger loss of fat and liver mass, resulting in improved relative muscle-to-body-weight ratios and preserved or enhanced physical function.

If you are using incretin-based medications for weight loss, expect some loss of absolute muscle mass, but do not panic about 'wasting.' The medication preferentially burns fat and liver fat, which improves your muscle-to-weight ratio. Your strength and endurance often improve because you are carrying less weight. To maximize muscle retention, prioritize resistance training and adequate protein intake, as the drug itself does not protect muscle mass but does not disproportionately destroy it either.